had to drive it some to make it get worse then the codes appeared...

5 of them, consisting of low res pulse failure, high pulse fail, est ground circuit failire ect

basically opti....it does this after the car idles a few minutes at a stop, so im poretty sure its heat related..

question, does anyone know what part is getting hot and failing? is it the optical sensor or what?

ive got another opti sitting right here that idles and drives perfect, but we thought was causing a high rpm studdar (bucks the car back and forth at 4500+) can i remove parts from one a fix the other? or even clean the one i have?

i hate this, its the FIRST opti problem ive ever had besides breaking rotors!

 

YEAH, YOU SHOULD BE ABLE TO TAKE IT APART AND SWAP PARTS. I'VE TAKEN EM APART BUT NEVER HAD AN OPTI GOOD ENOUGH TO CHANGE PARTS IN. ALTHOUGH I DID SAVE A GOOD OPTI SENSOR.

 

changed the opti didnt fix it...what else could it be? icm? coil any way to test it? goana check codes again tomaro although ses light aint on...what else is in the low res pulse circuit/ground fault where does it ground to?

 

I had a harness problem off the opti that did the same thing . It would up and die at a light or start to missfire real bad before dieing than i'd play withe pigtail to the opti it would work fine again

 

What were ALL 5 codes?

 

man ive never had a problem i couldent track down...im goana go check the codes again monday....
i though i fixed it the coil bracket was loose and those grounds didnt have good contact...i thought was the problem(after i swapped optis)
its still doing it, not as bad though, makes me think i have another ground problem...

once the temp gets to half 215 it starts to spudder down then the iac opens and it revs comes back down sits for 30 seconds or so then does it again and the 2-3 or 4th time it will die...sometimes taking 30 seconds to 2 minutes to restart....

 

there is a mod to space the icm and coil away from the engine
called an icm cooling mod

has somethign to do with the icm and or coil getting too hot to function. you may try this to see if it fixes your problems i really no nothing of this fix but.. if it is a "heat" issue id say this would be a good starting point

shoebox has a website with this fix on it.. may or may not work and if it dont work the coil and or icm may be bad.. or you may be able to find out which or what and just replace the part but in any case this mod seems like a good one here is the website hope it helps

ICM COOLING MOD - http://shbox.com/1/4th_gen_tech2.html#ICM_cooling

btw just got my fans tuned down for a 160 thermostat fans kick on at 185 and 195 now
i love it... the stock lt1 high heat is just asking from problems on lots of stuff.. ne ways would be a good thing to have done

 

i need to get a thermostat and already have a electric pump...this is my 4th moded 4th gen....i wanna get a tune but i cant believe the price for just basic mods....

i think i have an extra icm, ill put it on there and space it from the motor...

 

hope it works out i have never done it and dont know much about it i just stumbled across it the other day and still had it on the brain

i got a pretty good deal on my tune here is what i got

3 pass dyno tune
fan temps changed (185, 195)
adjustment for 3.73 rear end (spedometer fix)
tuned for 160 thermostat
skip shift light - off
air pump - off
smog pump - off
egr - off
rear o2's - off
air fuel ratio tweaked

price: $125

my car did 283 rwhp after last tune and run and 307 torque
the operating temp of the test was like almsot 108degree's in the building (sucks)

this was before i put my ram air box on (was factory)

i figure now in a more reasonable temp im prolly around 300 at rear wheels with the ram air thats what im guessing ne ways (hope) lol

i figure my car did pretty good tho for the lil bit of stuff i have done to it (below)